[Yoga] Initial commit for supporting Yoga-powered layout calculation. (#2982)

* [Yoga + AsyncDisplayKit] Initial commit for supporting Yoga-powered layout calculation.

Because this results in ASLayout objects, it preserve support for automaticallyManagesSubnodes
as well as the animated transition system. More work remains to vet performance of the new mode,
and it will remain in +Beta for the forseeable future.

I'm not sure that this should ever be used as the primary ASDK layout system, but it should remain an
option for some apps to experiment with if they require an implementation that more strictly mirrors
W3C standard Flexbox.

* [Yoga] Improve usage of ASHierarchyState to ensure simultaneous yoga layouts can't happen.

* [Yoga] Strictly minimize the impact of the Yoga integration on existing code.

Created new file ASDisplayNode+Yoga.mm, reduced size and number of integration points in core code.

* [Yoga] Figured out how to further reduce ASDisplayNode.mm impact by allocating _yogaNode in property accessor, and changing all accesses to use the property.

Author: appleguy

AsyncDisplayKit.podspec

@@ -44,18 +44,25 @@ Pod::Spec.new do |spec|
   end
 
   spec.subspec 'PINRemoteImage' do |pin|
+      # Note: The core.prefix_header_file includes setup of PIN_REMOTE_IMAGE, so the line below could be removed.
       pin.xcconfig = { 'GCC_PREPROCESSOR_DEFINITIONS' => '$(inherited) PIN_REMOTE_IMAGE=1' }
       pin.dependency 'PINRemoteImage/iOS', '= 3.0.0-beta.7'
       pin.dependency 'PINRemoteImage/PINCache'
       pin.dependency 'AsyncDisplayKit/Core'
   end
 
   spec.subspec 'IGListKit' do |igl|
+      # Note: The core.prefix_header_file includes setup of IG_LIST_KIT, so the line below could be removed.
       igl.xcconfig = { 'GCC_PREPROCESSOR_DEFINITIONS' => '$(inherited) IG_LIST_KIT=1' }
       igl.dependency 'IGListKit', '2.1.0'
       igl.dependency 'AsyncDisplayKit/Core'
   end
 
+  spec.subspec 'Yoga' do |yoga|
+      yoga.dependency 'Yoga', '1.0.2'
+      yoga.dependency 'AsyncDisplayKit/Core'
+  end
+
   # Include optional PINRemoteImage module
   spec.default_subspec = 'PINRemoteImage'
 

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -177,6 +177,7 @@
 		8BBBAB8D1CEBAF1E00107FC6 /* ASDefaultPlaybackButton.m in Sources */ = {isa = PBXBuildFile; fileRef = 8B0768B21CE752EC002E1453 /* ASDefaultPlaybackButton.m */; };
 		8BDA5FC71CDBDF91007D13B2 /* ASVideoPlayerNode.h in Headers */ = {isa = PBXBuildFile; fileRef = 8BDA5FC31CDBDDE1007D13B2 /* ASVideoPlayerNode.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		8BDA5FC81CDBDF95007D13B2 /* ASVideoPlayerNode.mm in Sources */ = {isa = PBXBuildFile; fileRef = 8BDA5FC41CDBDDE1007D13B2 /* ASVideoPlayerNode.mm */; };
+		90FC784F1E4BFE1B00383C5A /* ASDisplayNode+Yoga.mm in Sources */ = {isa = PBXBuildFile; fileRef = 90FC784E1E4BFE1B00383C5A /* ASDisplayNode+Yoga.mm */; };
 		92DD2FE61BF4D05E0074C9DD /* MapKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 92DD2FE51BF4D05E0074C9DD /* MapKit.framework */; settings = {ATTRIBUTES = (Weak, ); }; };
 		92DD2FE71BF4D0850074C9DD /* ASMapNode.mm in Sources */ = {isa = PBXBuildFile; fileRef = 92DD2FE21BF4B97E0074C9DD /* ASMapNode.mm */; };
 		92DD2FE81BF4D0A80074C9DD /* ASMapNode.h in Headers */ = {isa = PBXBuildFile; fileRef = 92DD2FE11BF4B97E0074C9DD /* ASMapNode.h */; settings = {ATTRIBUTES = (Public, ); }; };
@@ -613,6 +614,7 @@
 		8B0768B21CE752EC002E1453 /* ASDefaultPlaybackButton.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASDefaultPlaybackButton.m; sourceTree = "<group>"; };
 		8BDA5FC31CDBDDE1007D13B2 /* ASVideoPlayerNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASVideoPlayerNode.h; sourceTree = "<group>"; };
 		8BDA5FC41CDBDDE1007D13B2 /* ASVideoPlayerNode.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASVideoPlayerNode.mm; sourceTree = "<group>"; };
+		90FC784E1E4BFE1B00383C5A /* ASDisplayNode+Yoga.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = "ASDisplayNode+Yoga.mm"; sourceTree = "<group>"; };
 		92DD2FE11BF4B97E0074C9DD /* ASMapNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASMapNode.h; sourceTree = "<group>"; };
 		92DD2FE21BF4B97E0074C9DD /* ASMapNode.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASMapNode.mm; sourceTree = "<group>"; };
 		92DD2FE51BF4D05E0074C9DD /* MapKit.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = MapKit.framework; path = System/Library/Frameworks/MapKit.framework; sourceTree = SDKROOT; };
@@ -893,6 +895,7 @@
 				058D09D8195D050800B7D73C /* ASDisplayNode.h */,
 				058D09D9195D050800B7D73C /* ASDisplayNode.mm */,
 				68B027791C1A79CC0041016B /* ASDisplayNode+Beta.h */,
+				90FC784E1E4BFE1B00383C5A /* ASDisplayNode+Yoga.mm */,
 				683489271D70DE3400327501 /* ASDisplayNode+Deprecated.h */,
 				058D09DA195D050800B7D73C /* ASDisplayNode+Subclasses.h */,
 				058D09DB195D050800B7D73C /* ASDisplayNodeExtras.h */,
@@ -1902,6 +1905,7 @@
 				34EFC76F1B701CF700AD841F /* ASRatioLayoutSpec.mm in Sources */,
 				254C6B8B1BF94F8A003EC431 /* ASTextKitShadower.mm in Sources */,
 				254C6B851BF94F8A003EC431 /* ASTextKitAttributes.mm in Sources */,
+				90FC784F1E4BFE1B00383C5A /* ASDisplayNode+Yoga.mm in Sources */,
 				509E68601B3AED8E009B9150 /* ASScrollDirection.m in Sources */,
 				B35062091B010EFD0018CF92 /* ASScrollNode.mm in Sources */,
 				8BDA5FC81CDBDF95007D13B2 /* ASVideoPlayerNode.mm in Sources */,

AsyncDisplayKit/ASDisplayNode+Beta.h

@@ -8,6 +8,7 @@
 //  of patent rights can be found in the PATENTS file in the same directory.
 //
 
+#import <AsyncDisplayKit/ASAvailability.h>
 #import <AsyncDisplayKit/ASDisplayNode.h>
 #import <AsyncDisplayKit/ASLayoutRangeType.h>
 #import <AsyncDisplayKit/ASEventLog.h>
@@ -20,15 +21,15 @@ void ASPerformBlockOnBackgroundThread(void (^block)()); // DISPATCH_QUEUE_PRIORI
 ASDISPLAYNODE_EXTERN_C_END
 
 #if ASEVENTLOG_ENABLE
-#define ASDisplayNodeLogEvent(node, ...) [node.eventLog logEventWithBacktrace:(AS_SAVE_EVENT_BACKTRACES ? [NSThread callStackSymbols] : nil) format:__VA_ARGS__]
+  #define ASDisplayNodeLogEvent(node, ...) [node.eventLog logEventWithBacktrace:(AS_SAVE_EVENT_BACKTRACES ? [NSThread callStackSymbols] : nil) format:__VA_ARGS__]
 #else
-#define ASDisplayNodeLogEvent(node, ...)
+  #define ASDisplayNodeLogEvent(node, ...)
 #endif
 
 #if ASEVENTLOG_ENABLE
-#define ASDisplayNodeGetEventLog(node) node.eventLog
+  #define ASDisplayNodeGetEventLog(node) node.eventLog
 #else
-#define ASDisplayNodeGetEventLog(node) nil
+  #define ASDisplayNodeGetEventLog(node) nil
 #endif
 
 /**
@@ -147,4 +148,38 @@ typedef struct {
 
 @end
 
+#pragma mark - Yoga Layout Support
+
+#if YOGA
+
+@interface ASDisplayNode (Yoga)
+
+@property (nonatomic, strong) NSArray *yogaChildren;
+
+- (void)addYogaChild:(ASDisplayNode *)child;
+- (void)removeYogaChild:(ASDisplayNode *)child;
+
+// This method should not normally be called directly.
+- (ASLayout *)calculateLayoutFromYogaRoot:(ASSizeRange)rootConstrainedSize;
+
+@end
+
+@interface ASLayoutElementStyle (Yoga)
+
+@property (nonatomic, assign, readwrite) ASStackLayoutDirection direction;
+@property (nonatomic, assign, readwrite) CGFloat spacing;
+@property (nonatomic, assign, readwrite) ASStackLayoutJustifyContent justifyContent;
+@property (nonatomic, assign, readwrite) ASStackLayoutAlignItems alignItems;
+@property (nonatomic, assign, readwrite) YGPositionType positionType;
+@property (nonatomic, assign, readwrite) ASEdgeInsets position;
+@property (nonatomic, assign, readwrite) ASEdgeInsets margin;
+@property (nonatomic, assign, readwrite) ASEdgeInsets padding;
+@property (nonatomic, assign, readwrite) ASEdgeInsets border;
+@property (nonatomic, assign, readwrite) CGFloat aspectRatio;
+@property (nonatomic, assign, readwrite) YGWrap flexWrap;
+
+@end
+
+#endif
+
 NS_ASSUME_NONNULL_END

AsyncDisplayKit/ASDisplayNode+Subclasses.h

@@ -232,8 +232,8 @@ NS_ASSUME_NONNULL_BEGIN
 /** @name Observing node state changes */
 
 /**
-  * Declare <ASInterfaceState> methods as requiring super calls (this can't be required in the protocol).
-  * For descriptions, see <ASInterfaceState> definition.
+  * Declare <ASInterfaceStateDelegate> methods as requiring super calls (this can't be required in the protocol).
+  * For descriptions, see <ASInterfaceStateDelegate> definition.
   */
 
 - (void)didEnterVisibleState ASDISPLAYNODE_REQUIRES_SUPER;